Improvement in machinery for threading screws



3 Sheets$heet 3. C 1). ROGERS. MACHINERY FOR THREADING SCREWS. No. 177,282. Patented May 9,1876.

HIIIHI lIIIllQ IIIIIHHIIAYYi/l N PETERS, PHOTOUTNOGRAPHER, WASHINGTON, D. C.

IINITED STATES PATENT OFFICE;

CHARLES D. ROGERS, OF PROVIDENCE, RHODE ISLAND.

IMPROVEMENT IN MACHINERY FOR T-HREA DING'SC REWS.

Specification forming part of Letters Patent No. 177,282, dated May 9,1876 application filed April 22, 1876.

To all whom it may concern Be it known that I, CHARLES D. ROGERS, of Providence, in the'State of Rhode Island, have invented "certain new and useful Improvements in Machinery for Shaving, Pointing, and Threading Wood-Screws, of which the following is a specification:

The invention consists in the employment of a multiple tool in each or either of the operations of shaving, pointing, and threading the screw in machines in which a single tool has been used'heretofore; in devices for bringing 'the difl'erent cuttingparts of the multiple tool into operation successively as they may be required, with especial reference to the continued use and adjustment of the tool as'it wears away; and in a contrivance by which the times at which the different cutting parts of the tool are brought into operation may be determined automatically.

It is well known that in shaving, pointing, or threading screw-blanks the tools employed for those operations become dull after operating upon a small number of blanks, and that there is great loss .of time and skilled labor in changing the dull for a sharp tool, and in ad ju-stin g the new tool for further work.

The object of my invention is to remedy this difficulty, and for that purpose I have so cut teeth in circular steelplates that each tooth, when brought up to the blank by partially revolving the plate, shall present to the blank thesame cutting edge or edges presented by the ordinary single tool and I have also-devised mechanism, which maybe embodied in the ordinary shaving, point-ing, or threading machine, for successively presenting the different teeth of the plate-to the blank with sufticient exactness at required times.

- In the drawings forming a part of this specification I have shown several multiple tools, which I have made for respectively shaving, pointing, and threading the screw, and the mechanical devices for operating and adjusting such-tools as embodied in a threading-machine, that machine differing from pointing and shaving machines only in unimportant particulars.

In thcdrawings, Figure l is a plan of said threading-machine. Fig. 2 is a front elevation 9 and 10 are, respectively, a plan and a section of a multiple pointing-tool. Figs. 11 and 12 are the same views of a multiple shaver. Figs. 13 and 14. are the same views of a multiple threader. Y

A is the frame of the machine. B is the spindle, with any ordinary means of holding the screw-blank. G is the cam-shaft, driven from the spindle, as shown, and carrying the principal cam D. E is the tool-post, having all the motions of the tool-post in ordinary threading-machines. Its motion to give the lead to the screw is derived from a lift on the side of the cam D, acting upon the end of'a rocking-shaft, e, to which the tool-post is rigidly connected, and which rocks and slides in bearings projecting from the table or frame, a spring, 8, attached to the'frame and to a rigid elbow-projection, e, from the tool-post, keeping the end of the rock-shaft c in contact with the cam.

The rocking of the tool-post forward, to carry the tool forward toward the axis of the blank, is governed by a small cam, F, under the table,-which is revolved by a ratchet, f, rigidly attached to it, and a pawl, 12, attached to a sliding bar, G, which in turn is operated by a wedge-shaped projection, d on the periphery of cam D, and a spring. As the cam F revolves,'it gradually raises a bar, H, lying on the table, which barin turn lifts a former, I,

the former I in turn lifting the elbow-projection 6'. A spring, 8, draws back the tool-post I when the cam F permits.

'When the invention is applied to a shaving or a pointing machine the mechanism forgiving the lead to the screw is omitted, and the cam F acts directly upon the elbow-projection 0. I

In the threading-machine thc'upp'er surface of the former I is so shaped as to cause the point of the screw to be threaded, the end of the elbow-projection e traveling along that surface. The tool is released from the blank between the successive cut by means of a pro-. jection on the lower side of the former I, and a projection on the upper side of the bar H. and a sliding motion given to the bar H. When the projections are disengaged the spring 8 draws back the.tool from the blank. WVhen they are engaged the tool-post and tool are directly under the control of the cam F. The bar H gets its sliding motion from a lever, H, to which it is pivoted at h, and which,

in turn, is pivoted to the table, and is vibrated once in every revolution of the cam D by havin g a projection from it enter a depression, d in the side of the cam, the said projection being constantly held up against the side of the cam D by a spring attached to the bar H and the table. J is a rest for the blank, and is rigidly attached to a rock-shaft,j. A spring coiled around the shaft j keeps the rest back from the blank. The rest J is held up to the blank by means of a pin, k, screwed into an arm. clamped to the rock-shaftj, so as to form an elbow, the lower end of the pin 7c resting upon the upper surface of a ratchet, L, under the table, revolved by means of a pawl, 1 the pawl being operated by a sliding bar, In, having a pin engaging two projections on one side of cam D. There is a depression in the upper surface of the ratchet L, into which the pin l0 enter'souce in every revolution of the ratchet, remaining there during a partial revolution of cam D to permit the rest J to fall back from the blank.

Thus far, with the exception of the multiple tools as units. I have merely described ordinary screw machinery, to which my inventions are applicable. 1 proceed to describe the manner in which I have in-grafted my inventions upon such machines.

P is a multiple tool, secured by a set-screw to a shaft, 19, which revolves in bearings in the tool-post E. M is an index-whe.el, having projections or teeth corresponding in number and position to the teeth of the multiple tool. The indexavheelis mounted on the sameshaft as the multiple tool, being keyed thereto; and it is obvious that by turning'theindex-wheel one tooth forward, and lockin g it by any ordinary means, the multiple tool will be turned one tooth forward and a new tooth will be presented to the screw-blank ready to operate upon it; and this operation may be continued by an operative of the most ordinary'skill until all the teeth of the tool have been used to such a degree as to require sharpening- As the teeth rapidly wear away in use, however, it is desirable to have in the machine some contrivance for bringing a repaired tool up to its work, or for adjusting the tool whatever may be its diameter. Such a contrivauce consists of a quadrant plate, N, loose upon shaft 1), and

a wedge-shaped piece, a, with a notch, into which the projecting end of thevibratin g arm m enters, as shown twopins, r andr, and two springs, as shown.

A partial revolution of the tool is made by raising the vibrating arm m. This causes the pawl n to enter between two teeth of the index-wheel M, and at the same time the inner end of the vibrating arm mentors the notch of the wedge-shaped piece a, andpulls that piece down, thus disengaging the tooth of when the tooth of the locking-pawl o flies back between the teeth of theindex-wheel. The vibrating arm m is then permitted to fall back upon the pin r, the spring bringing. its at tached pawl at back. with it. j

As the mechanism for revolving andlocking the tool just described (more especially the locking device) is secured to the quadrant, it follows that, by changing the position of the quadrant on the tool-post, by means, of the set-screw and slot before referred to, thetool may be adjusted to any requiredposition, and

it follows, further,-that the adjustment having been made for onetooth of the tool, it is made for all the teeth.

It remains to describe an automatic device for operating the vibrating arm ,m. i.

This arm is automatically pulled down by force of a spring, 5 It is lifted by a T-shaped bar, R, working up andgdown. in a socket. in the table, the bar R being lifted by an arnnt, clamped to a rocking shaft, T, under thetable, the arm t being kept away from the bar R by force of a spring coiled on the shaft, except when the shaft is rocked by a pinion, t, oper, atedby a rack, to, when the latter descends, the rack w being in turncaused: to descend, at required intervals,by a cam, W, loose upon the spindle, and. having a slot in its Ysidei to.

recieve the pin 11 of aspring-clutchgV, keyed to the spindle. Y is a swinging arm pivoted to the frame, asshown. .It is pulled down at proper intervals by a rod, 0, whose lowerend is attached to a swinging lever, g, pivoted below the table, and operated by aprojection,

l upon the lower side of the ratchet-wheel L, the means of turningwhich have already been described. The swinging arm Yvhas ionione side a projectiomy, serving as a doublecam for a purpose. next to bedescribed. i

The springclutch V has a spring-pin ,"v,.one half of the end of which isagainst the face. of

the cam W, or, when the pinis unlocked, enters the slot in cam W, while; the other halfor the end is uncovered, or, whenthe pin is unlocked,

presses against the side; of the doublelcam y.

The spring-clutch pin '0 formost of thetime is held in place by a second pin, x,.also having remse I 3 irom time to time, is drawn out to release the clutch-pin by a third pin, 2, rigidly secured to it at right angles, and working in a slot in the clutch V, as shown, this third pin 2- being moved in the slot by striking against the camshaped periphery of the double cam '1, when the arm Y is drawn down. The operation of theclutch is, accordingly, as follows: At intervals, determined by the projection on the lower face of theratchet L, the swinging arm Y falls, and the cam on the periphery of the double cam y moves the pin 2 in its slot, thereby releasing the clutch-pin c, which enters in part the slot of cam W 5 but, while the clutch Yand cam W are making arevolution together, the pin 1; strikes the cam on the side of the double cam 3 and is gradually drawn back into its recess in the clutch V, thus disengaging the clutch V and cam W. The arm Y is raised by a spring coiled around the rod 0.

i As before stated, the rack 20 is caused to descend by the cam W acting upon its upper end. When released from the cam it rises by force of the spring before referred to, coiled on the rocking shaft T.

When the vibrating lever m is not operated automatically it should be provided with a suitable handle.

I claim 1. In machines for shaving, pointing, or threading screws, a multiple tool'mounted on the tool-post, and so governed by a locking index-wheel that, by turning forward andlocking the index-wheel, a new tooth may be presented to a revolving blank, and caused to operate upon it, substantially as described.

2. In machines for shaving, pointing, or threading screws, a multiple tool having bearings in the tool-post, in combination with an index-wheel and mechanism for making and preserving the adjustment, whatever may be the diameter of thetool, substantially as described.

3. In machines for shaving, pointing, or threading screws, a multiple tool revolved and adjusted substantially as described, in combination with mechanism, substantially as described, for controlling the revolution of the tool automatically.

WILLIAM W. SWAN,- H. G. OLMsTED. 

